1. Field of the Invention
The invention concerns a machine for cleaning beaches.
2. Description of the Prior Art
A known beach cleaning machine comprises a self-propelled vehicle carrying a tippable skip, a front-mounted apron adapted to pivot about an axis perpendicular to a longitudinal axis of the machine, means for adjusting the inclination of the apron whose lower forward end is provided with a blade adapted to dig into the sand and to the rear of which extends a first grid conveyor discharging onto a conveyor belt adapted to convey detritus picked up by the apron to the skip, drive means for the conveyor, a second grid conveyor above the first grid conveyor provided with paddles and whose upper end is pivoted to one end of two links whose other ends are pivoted to the apron, rams operating on the links, rams operative between the lower end of the second grid conveyor and the apron and a motor adapted to drive said the grid conveyor in the opposite direction to the first grid conveyor.
A machine of this kind has a number of drawbacks. In particular, seaweed and other material picked up from beaches are viscous and sticky so that sand adheres to it. Therefore, this known machine picks up a significant quantity of sand.
It is desirable that only a little sand should be picked up with this material. First, only a small amount of sand should be picked up because sand is heavy and rapidly fills the skip. Second, if too much sand is picked up, a significant quantity of sand may be removed from the beach, whereby a shortage of sand may result.
Another drawback of a machine of this kind is that it is difficult to drive, especially on roads.